Hey guys.. I registered to share with this you so hopefully it helps someone else. I've been having all the same issues that are described here and starting compiz like this seems to have solved it for the most part:
compiz --replace --sm-disable ccp
This will create a new profile and you'll have to redo all of your settings, but this seemed to work for me. I don't know whether it was --sm-disable or the ccp, but this combination cures the crash that happens when I try to shutdown/restart/sleep the computer.
Hope that helps!